As the Universal Serial Bus (USB) approaches its 13th birthday, like other adolescents it’s eager to start thinking and acting independently.

For the USB, this means chucking the cable and connecting to a wide variety of printers, keyboards, hard drives and other office peripherals without wires.

The idea behind Wireless USB (WUSB) is simple and seductive. Instead of connecting directly to a computer, WUSB uses ultrawide band (UWB) technology to wirelessly connect a USB peripheral to the system.

UWB spreads the data out over a huge swath of spectrum, rather than blasting a powerful signal in a small portion of the spectrum, as is the case with cell phones, Bluetooth and Wi-Fi.

Because the signal is just above the background-noise level, WUSB is able to move a good amount of data without interfering with any of your other wireless gear, like a Wi-Fi router, a cell phone or a Bluetooth headset.

On paper, WUSB matches the USB 2.0 limit of 480Mbit/sec. of throughput, but don’t expect this level of performance from most real-life setups.

As is the case with most communications technology, WUSB’s actual performance tends to be lower, closer to 25Mbit/sec. at a distance of 5 feet. That’s about one-quarter the speed that a cabled USB connection provides.

To get the two devices to work together, the transmitter and base station need to be paired. This process takes about 10 or 15 seconds and only needs to be done once. The next time the two devices meet, they can automatically connect. WUSB has a practical range of up to about 35 feet.

Not much available yet

At the moment, there are only a handful of WUSB products available. These include cable replacement kits, USB hubs and video extenders for linking a computer to a projector or monitor.

In-Stat analyst Brian O’Rourke forecasts that sales of WUSB devices will grow quickly over the next few years. In 2007, sales were a piddling 100,000 units, which he thinks could increase to as much as 190 million units by 2012.

A big step forward will be building WUSB into a generation of peripherals, including printers, scanners, media players and displays. That’s starting to happen. Later this year, Imation Corp. will introduce a WUSB external hard drive, Toshiba will have a WUSB docking station and projectors and monitors will be available from Asus, Samsung and others. Currently, there are about a dozen notebooks available with WUSB built in, but they are nearly all special-order items that are hard to actually get. As a result, every WUSB device comes with a USB dongle that contains a transmitter and plugs into the computer.

The remote device itself — which contains the WUSB base station — is powered by an AC adapter; some of the WUSB products add external antennas that can be aimed to grab the strongest signal while others have them buried inside.

To see what’s possible with WUSB, I collected several currently available WUSB devices: hubs by D-Link and IOGear; the Cables Unlimited Wireless USB Adapter Set; and two video kits: Imation’s Wireless Projection Link and IOGear’s Wireless USB to VGA kit.

I tried them out using a Dell Vostro 1510 notebook (with which I used the supplied dongles) and a Fujitsu LifeBook A6220 notebook (which comes equipped with WUSB).

Wireless USB has great potential to cure desktop clutter and end the hassle of stashing cables under carpets or taping them to walls, but it’s still in its infancy. In other words, don’t throw your USB cables away just yet.

How we tested

The beauty of the Wireless USB standard is that rather than having to buy new wireless equipment, you can plug your favorite wired USB peripherals into the wireless hub, and they’re connected to your PC or laptop without a wire in sight.

I tried the wireless hubs and cable kit with nine USB peripherals at a distance of 5 feet from my Dell Vostro 1510 test bed.

With the DVD drive connected, I listened to an audio CD with an ear to whether there were any dropouts, skips or muddled sound.

Finally, with the CD still playing, I walked away from the WUSB product with a connected notebook in hand and noted where the system lost its connection. Then I walked back toward the hub to see if it automatically reconnected.

Finally, I measured the throughput for each hub kit using a Passmark USB2.0 Loopback Plug and Passmark’s USB2Test software, which sends data out and times how long it takes to return to the notebook.

The system logs nine tests every second for a minute and tabulates the results.

These figures, however, represent the upper theoretical performance limit you can expect from the hub or cable replacement product.

To get a real-world result, I connected a 500GB Western Digital My Book USB external hard drive and moved a 209MB folder with 250 files in it and timed how long it took to move all the data to the notebook.

For comparison purposes, I repeated the tests with the Fujitsu LifeBook A6220.

For the video, I connected each video kit to the Vostro 1510 notebook and a Dell 17-in. LCD monitor. (I repeated each procedure with a Vizio 47-in. TV and then used the Fujitsu LifeBook A6220 notebook that has WUSB built in.)

I used each device to extend and then mirror the notebook’s desktop to the monitor. I then walked away from the transmitter and noted where it lost contact. Next, I walked back to see if the system would reconnect.

I watched online and DVD videos and looked for artifacts, delay or dropouts in the video.

Wireless USB hubs

Neither of the hubs that I tested offered speed, range and compatibility at the right price.

Both come with dongles that plug into your system’s USB port, but the IOGear’s device includes a swivel extender and the D-Link hub includes a short USB extension cord.

Setting both of them up was stress-free, with integrated software installations and detailed instructions.

Each took about 5 minutes to install; the devices paired in less than 15 seconds and connected on the first try. Although both dongles have hidden antennas, their hubs have adjustable ones that can be aimed; the IOGear’s antenna is also removable.

D-Link Wireless USB Starter Kit

They both come with software that sets up and monitors the wireless connection and shows its signal strength. IOGear’s software has the signal strength in a pop-up window.

It also shows a list of which devices are connected and which drive letters they are using — a great way to keep an eye on your peripherals and help troubleshoot an errant connection.

The beauty of WUSB technology is that it lets you use your current USB devices, although neither of the hubs achieved a perfect score with the nine devices I threw at them. The IOGear wireless hub could not connect to an iPod, while the D-Link hub couldn’t connect with my external DVD drive.

Using a Passmark USB2 loopback device (which measures the theoretical peak throughput), I measured the devices’ performance at a range of 5 feet. The IOGear did somewhat better, moving 202Mbit/sec. as compared to D-Link’s 170Mbit/sec. When I plugged an external USB hard drive into each hub, they came in neck and neck: The IOGear hub moved 27.5Mbit/sec., very slightly ahead of the D-Link’s 27.2Mbit/sec. Note that these results are a lot slower than the 93.4Mbit/sec. I got when I plugged the hard drive directly into the computer using a 6-ft.-long USB cable.

As far as range goes, the IOGear hub lost its connection at 25 feet, barely outdistancing the D-Link hub, which lost contact at 23 feet. The good news is that both reliably reconnected as soon as they were back within range. They both worked with the WUSB equipped Fujitsu LifeBook A6220 notebook, although it sometimes took a couple of tries to connect.

While I find the lack of perfect compatibility with the iPod a potential problem, my choice is the IOGear hub, mainly because of price — the IOGear hub costs $130 while the D-Link hub does roughly the same thing for $200.

While it provides a single USB port, as opposed to the four provided by the wireless hubs, you can always connect it to a normal hub.

It comes with a USB dongle, a base, an AC adapter and the usual drivers and connection software. A snap to set up, the Cables Unlimited kit was up and running in about 5 minutes. My only problem was with its 3-in. mini CD, which kept popping out of the Vostro 1510’s slot-loading optical drive. Despite this issue, the kit paired on the first try and was beaming data moments later.

Cables Unlimited Wireless USB Adapter Set

Longer and narrower than the other WUSB dongles, the Cables Unlimited device swivels and tilts but gets by without an external antenna.

The printed setup cartoon that’s included offers a simple explanation of how to get started, but I prefer the detailed instructions that came with the other WUSB products.

The associated software offers basic information, including the host’s ID and signal strength, but doesn’t list what devices are actually connected. On the other hand, of all the WUSB connection devices I looked at, only the Cables Unlimited kit aced my compatibility test, connecting to all nine USB devices without a snag. On the downside, the USB slot and power jack on the receiver’s base are so close that I had to use a USB extension cord when plugging in my USB voice recorder.

When I measured performance at a range of 5 feet with the USB loop-back device, I got a scorching 327Mbit/sec. (the top speed of all the products reviewed here).

Keep in mind, though, that this speed is the theoretical peak that the device can deliver. With the external hard drive connected, the Cables Unlimited kit could move only 15.7Mbit/sec.

The Cables Unlimited WUSB kit is also the long-distance winner — it was able to stay connected at 38 feet, more than 10 feet longer than the hubs. It reconnected automatically as soon as it was back within range and worked well with the WUSB-equipped Fujitsu LifeBook A6220 notebook (although it — like the others — sometimes took a couple of tries to connect).

At $100, the Cables Unlimited WUSB kit is one of the cheapest WUSB products around (although it comes with a one-year warranty, not the three years of coverage provided by D-Link and IOGear).

Although the Cables Unlimited Wireless USB Adapter Set isn’t the fastest connection around, it has an impressive range and can work with all sorts of different USB devices.

Wireless USB video

Video cables have finally met their match. Whether it’s for a desktop PC monitor or a notebook that connects to a projector, WUSB video technology can put video on screen without the wires. However, if you want to hear what you’re playing, you’re going to have to stay wired — today’s products can’t work with audio. (Later this year, IOGear plans to introduce a WUSB video kit that includes a separate receiver for audio.)

I looked at Imation’s Wireless Projection Link and the IOGear Wireless USB to VGA Kit. Both can connect just about any PC to a display or projector without a cable. Both came with a USB dongle, a receiver for the monitor, an AC adapter and a software CD. The Projection Link’s dongle snaps into the receiver for easy travel and can be used with a PC or Mac without loading any software. It works better with the drivers (which only work with PCs); you get smoother video, less lag and lower-system requirements.

Imation Wireless Projection Link

Getting it set up is a bit rough, though; the installation procedure is complicated and requires running several different programs. Set aside 20 or 25 minutes to get it working. By contrast, IOGear’s installation was a breeze and took 5 minutes.

Each video extender paired with its USB dongle in between less than 15 seconds, and quickly connected with my Dell 17-in. monitor and a Vizio 47-in. TV.

You can’t imagine the feeling of liberation that comes with connecting to a monitor or projector wirelessly. Free to roam about the room, it’s perfect for trainers, presenters and those who just can’t sit still. Both products have a slight lag between an action on the notebook and when that action shows up on screen, but it is tolerable.

IOGear Wireless USB to VGA Kit

Both video products gave me the choice of extending my notebook’s desktop or mirroring it, and each device has customization software that sits in the system’s task tray.

The IOGear video kit is the resolution winner, with the ability to display 12 different monitor settings and up to 1,600 by 1,200 resolution, including several wide-screen options. By contrast, the Projection Link has only three choices that max out at 1,280 by 1,024 and is limited to the traditional 4:3 aspect ratio formats.

However, the Imation Projection Link has three features that the IOGear lacks: it can freeze the view, blank the screen and add a personal start-up image. It also frequently warned me that the system was running out of virtual memory, a problem I didn’t encounter with any of the other four WUSB products.

The IOGear video kit has antennas on both the dongle and the base that can be aimed and removed, while the Imation gear only had an antenna on the base that can be aimed, but not removed. With a range of 30 feet, the IOGear bested the Projection Link’s 15-ft. range. Both reconnected automatically and worked with the Fujitsu LifeBook A6220. Of the two video products, my choice is the IOGear equipment for its easy setup, superior range and removable antennas. Personally, I can’t wait for the version that adds audio, making it a clean sweep.

Conclusion

For the most part, WUSB is an impressive technology that can put an end to the tyranny of cables. It’s reliable and has just enough range and throughput to be useful in an office.

However, there aren’t yet enough devices to make it worthwhile at this point. Basically, the technology needs to mature and become more widespread before it can enter the mainstream.

If that happens, in a few years, we might live and work in a Wireless USB world, where cables seem so 20th century.

When you get back from a business trip, for instance, your notebook would sense the WUSB signal, automatically dock and put all your files where they need to be while connecting to a big-screen monitor, keyboard and mouse. In other words, as near to mobile nirvana as it gets.

Brian Nadel is a freelance writer based near New York and is the former editor in chief of Mobile Computing & Communications magazine.